Condoms in the form of a sheath, are worn over the penis to help prevent pregnancy and/or transmission of sexually transmitted diseases such as syphilis, gonorrhea, chlamydia infections, genital herpes and AIDS, for example, during sexual intercourse. Condoms are typically composed of thin barrier membranes of latex or similar elastomeric materials for optimizing sensitivity, tactile sensation and heat transference during intercourse. Recognizing the material and thinness that condoms typically comprise, the risk of a break or tear in a condom during sexual intercourse is always a significant concern in condom design and manufacturing.
Generally, condoms are made by a dipping process, whereby an appropriately dimensioned mold or mandrel is dipped into a latex rubber emulsion, for example, formulated with various curing (vulcanizing) agents and accelerators. The mandrel, coated with the latex rubber emulsion, is withdrawn and subjected to elevated temperatures for drying and curing of the latex rubber to achieve the desired physical properties. The cured condom is then stripped from the mandrel and rolled into a toroidal configuration for packaging. The condom is donned by unrolling it down the shaft of the penis.
It is known in the art to include cross ribs or other projections along internal or external surfaces of a condom for the purpose of stimulating the male and female during sexual intercourse. The textured surface of such condoms provides increased frictional and tactual kinetics for enhancing tactile sensation and stimulation. Typically, the ribs or projections are integrally formed on a surface of the condom resulting from the use of grooves or notches etched in the surface of the mandrel during the dipping process. The design of the ribs or projections ranges from interrupted rings canted with respect to the radial plane to helical patterns of various ribbed arrangements.
A problem to be overcome in designing and manufacturing ribbed/textured condoms is to avoid breakage or tearing during use. The problem is linked to the configuration of the grooves or notches for forming the ribs or projections in the mandrel during the dipping step previously described. When a smooth mandrel is withdrawn from the latex rubber emulsion, the uncured liquid latex rubber flows downward for ideally forming a uniform coating or layer. However, as the uncured latex rubber readily flows along the surface of a notched mandrel, the grooves or notches in the mandrels interfere with the uniform flow causing potential backfill problems which can result in the formation of undesirable weak spots in the condom and nonuniformity in wall thickness.
It would therefore be a significant advance in the art of condoms to develop a textured condom which provides enhanced tactile sensation to both the male and female partner while avoiding the weak spots and the resulting failures that can be associated with prior art ribbed/textured condoms. An additional benefit of the condoms of the present invention is that these condoms are capable of being fabricated in a cost efficient and effective manner, using known conventional methods of condom production. This enables manufacturing facilities to produce the improved condoms with minimal retooling and/or changes to existing equipment.